- 2 settimane fa
Videointervista a Paul Debvec, “maestro della luce di Hollywood”, a capo dell’Institute for Creative Technologies in California. Dall'edizione 2013 del VIEW Conference di Torino.
Categoria
🎥
CortometraggiTrascrizione
00:05The techniques you created in the field of lighting are the basis of most movies.
00:09Would you tell us about your job in this sector?
00:14So I think the most impactful thing that I've done in the research area
00:19was to figure out how to capture light in the real world
00:22and then use it in the computer-generated world.
00:26So this is work that I did in the late 1990s.
00:30I'd been doing a lot of photography,
00:32and I'd realized that a normal digital image
00:37doesn't contain the entire range of light that's actually out there.
00:41Normally a digital image has pixel values,
00:45numbers that represent the brightness values that are in a certain range,
00:48but that light sources can far exceed this.
00:51So I came up with a way of taking multiple exposures of a scene
00:56from underexposed to overexposed,
00:57is putting them together and taking what were called high dynamic range images.
01:02And HDR photography has actually taken off quite a bit.
01:06There's even a feature on your iPhone that it says HDR on or HDR off.
01:11That has a bit of a connection to work that I did back then.
01:15But the most unique thing that I did with this is I realized that if you have a panorama
01:20that is shot in high dynamic range and covers the entire range of light that's out there,
01:26you've recorded what the light is like at that point in space.
01:29And that if you then use a lighting simulation technique that's physically realistic,
01:37you can use light in the real world to illuminate a computer-generated object.
01:41And I got very excited about that because that meant that I could take a real-world scene
01:45and put things into the scene, make them look like they were really there,
01:49reflecting the right light, casting the right shadows, having all the right shading,
01:54without having to artistically manipulate that.
01:57I didn't have the artistic training to do that.
01:59But to be able to do the answer correctly through technology was exciting.
02:04And I ended up using that in some of my own films back then.
02:09It was seen as a useful technique for Hollywood films, for the visual effects.
02:14And at this point, I think that it probably has been used in probably a couple hundred different films.
02:19So it's probably no movie that involves both live action and computer graphics
02:24that doesn't do some form of this image-based lighting process.
02:28Which one of the films you work for had the biggest impact on the field of visual effects?
02:34Hmm. Good question.
02:37So.
02:44Let's see.
02:47Well, so in my job, I work for a university.
02:50And our main goal is to write research papers and present them at conferences,
02:55usually the SIGGRAPH conference.
02:57It's nice to come to the VIEW conference, like we have here,
03:00and share some of the techniques with the Italian community
03:03and also interact with some of the other people in the movie industry.
03:09You know, the Matrix is seen as having a big influence on visual effects
03:14because it used photography to combine what has happened in the real world
03:23with what's happened in the virtual world.
03:24And the very story of the Matrix is about losing the boundary
03:30between what is real and what is virtual.
03:32It's about realizing that everything around you could be a computer simulation.
03:37And so there was a very nice marriage of technology
03:39between taking digital photographs of the real world,
03:44turning it into virtual scenes,
03:45and then inside the visual effects for this movie,
03:47turning it back into things that looked like the real world,
03:50except it was actually a simulation of the computer world.
03:53I think that pointed the way a lot to this merging of what is photographically acquirable
04:00and what can be simulated.
04:02And a lot of visual effects since then have been based on that.
04:06Which director you work with can give importance
04:09and gives at the best the visual effects in these movies?
04:13So I got to work with Alfonso Cuaron a little bit on the movie Gravity
04:17and see him directing actors that were inside the LED system to light their faces.
04:26And getting a believable performance for a scene in a movie,
04:32part of it is making sure that it's shot from the right angle.
04:36Part of it is making sure that the light is the right light that's on their face.
04:41I was happy that technology we had developed about taking light from a virtual set
04:45and then reprojecting it on the actor to get that light to look correct in the movie
04:50was useful for this film.
04:53But most importantly, you have to have what's happening to the actor
04:59be impacting how that actor is performing.
05:03And usually when an actor is on a set,
05:06they're having to imagine a lot of what's going on around them.
05:09And they have to play out the simulation in their head
05:11so they can react to something that isn't really happening to them.
05:14What I saw with Alfonso Cuaron working with the actors
05:18is that through his own energy and his own things that he says to the actors,
05:23he could really help convince them of what was happening to them,
05:27that they were in danger, that this thing was coming at them,
05:31that they might be losing hope, that this is going to be the end of them.
05:38And with all of the things that you see in a performance,
05:41it's about how are you reacting to the environment,
05:44how are you reacting to the light, how are you reacting to the physics,
05:47how are you reacting to the situation of the story.
05:50And whatever we couldn't simulate in technology,
05:53he was able to create in their minds through his directing.
05:56and that was amazing to watch.
05:59What will be the next progress in the field of visual effects?
06:03And on what aspect do you have to work in the next years?
06:07So we're seeing more and more computer-generated characters
06:11showing up in films and also video games.
06:14And when they're successful, it's usually because there's a real actor
06:19who's in a motion capture suit and maybe they have a helmet with a camera
06:25that follows their performance as they move around.
06:29The process of getting a real actor's performance onto a digital character
06:34is still far from perfect.
06:38The technology of tracking how their face moves in the video
06:42and then projecting it onto the digital characters so they move in the same way,
06:47it's not fully automatic right now.
06:50It can get you better than halfway there.
06:54But if you just watch what the answer of the technology is,
06:58it's not very convincing.
07:01What the actor was providing doesn't live on in the virtual performance.
07:05So you have to have currently a lot of trained animators fixing everything
07:09to add little curls to the lips,
07:12to add little twitches to the eyes,
07:14to make it look like the lips shoot forward when there's a breath of air.
07:19All those things don't get picked up with the technology right now.
07:22So that's what I think we need to do,
07:25is to make it so that what an actor is performing
07:28and what you can capture on video
07:29can get onto the computer-generated character
07:33faithfully, quickly, and automatically.
07:35We'll probably have to work on that one for another five years.
07:40The stereoscopic can't convince all yet.
07:43What do you think about the use of 3D
07:45and how does this affect your job?
07:50So I think that certain movies work very well in 3D.
07:53I thought Gravity is a great movie for 3D.
07:56And I knew it was going to be a great movie for 3D
07:58because I saw this IMAX film called Hubble 3D,
08:02which is shot with real IMAX cameras in the space shuttle
08:06when they went to repair this Hubble space telescope.
08:09When you have a big screen
08:11and the 3D action is about the right size
08:14for what you're seeing on the screen,
08:17it can be an enormously great effect.
08:20I think Life of Pi really benefited from the 3D
08:23because it was all about the isolation
08:26of this boy and this tiger on a boat.
08:28And in 2D, you just see the boat
08:30and then you see the water is like a flat blue line below you.
08:35In 3D, that water extends into the horizon
08:39and you get the sense that there's an enormous environment
08:41and there's just this tiny little speck in the middle of it.
08:44And that was very important for the story.
08:46So I think it's important for filmmakers to choose
08:49when to use 3D and when not to use 3D.
08:54A lot of our research is about trying to investigate new technologies
08:59that will provide a 3D experience without using the 3D glasses
09:03and be more like holographic projection around you.
09:09And to do that,
09:10you actually don't just generate one left eye and one right eye
09:14like you have in a 3D movie,
09:16but you have to generate hundreds of viewpoints all the way around.
09:19We want it so that if somebody moves their head to one side or to the other,
09:23that they'll get a sense of the motion of the scene as your head moves.
09:28This is called motion parallax.
09:30And it's a much stronger effect than binocular stereo,
09:34which is the fact that in a 3D movie,
09:36you get a different image to your left eye and your right eye
09:38that helps reveal depth.
09:40It's even more important when you move your head
09:42that you can see 3D.
09:45And in a 3D movie, if you're watching it
09:47and you move your head back and forth,
09:48nothing changes and it looks strange.
09:51So for our research, we're getting hundreds of video projectors,
09:55we're rendering off of computers,
09:56hundreds of points of view simultaneously.
09:58We reflect it onto the right kinds of screens
10:00and we are able to start to produce this kind of imagery
10:03that doesn't require glasses
10:04and it really looks like a 3D scene out there.
10:09What are you working on?
10:12So we're actually working on a couple of different things.
10:15One of our projects right now is in collaboration
10:19with the Shoah Foundation Institute at USC.
10:22This is a group that was set up by Steven Spielberg
10:25after he made the movie Schindler's List in the 1990s
10:29to record the stories of survivors of the Holocaust of World War II.
10:36And there have been tens of thousands of hours of videotape
10:41recorded of these people telling their stories,
10:44stories, but a lot of it's in standard definition
10:47and it's not done with the highest level of fidelity of recording.
10:53What we're working on is developing a new system
10:56to record somebody telling their story in holographic form.
11:02We're actually running 50 video cameras,
11:05all high definition simultaneously on them
11:07from different angles.
11:09Some of them zoomed in on the face, some on the hands
11:11to record a data set that could eventually project them holographically
11:16into a theater or a classroom to tell their story into the future.
11:21And some of the technology we're building for holographic projection
11:24that uses hundreds of video projectors
11:26will be able to produce vivid three-dimensional images of these people
11:30so that in 20 years when, unfortunately,
11:34we doubt any of them will still be around to tell their stories,
11:38we'll be able to have as close of a possible connection
11:42to their stories and to their physicality as we can.
11:47What is hot nowadays?
11:50What are the new techniques in this sector?
11:54Very good question.
11:57Let's see.
11:58So, in visual effects, something that's very hot now
12:03is using much more advanced lighting simulation based on real physics.
12:09If you go back, you know, 10 or 20 years,
12:12a lot of visual effects were done using artistry more similar to painting.
12:18You know, a good artist who's a painter can see light in their mind
12:22and imagine how it plays against the surfaces
12:25and actually paint all of the shapes and shading in a way
12:28that it will look realistic and believable.
12:31But it's slow to do it that way,
12:33and it's very difficult to do it for very dynamic scenes
12:36that will take place throughout a movie.
12:38So computers have gotten faster and faster
12:40to the point where now you can actually simulate the real physics
12:44of how light actually works in the world.
12:47You can simulate complex environmental illumination,
12:50lights coming from everywhere.
12:51It's bouncing from one surface to another,
12:53forming very complicated images in the camera.
12:56And movies like Pacific Rim, for example, or Gravity,
13:00are rendered using these advanced lighting simulation engines.
13:04This one that both of those films was rendered in is called Arnold.
13:08It's written by a Spanish friend of mine named Marcos Fajardo.
13:11And he started writing it in the year 1998
13:16when computers were still too slow to do this.
13:18But in the year 2013, with computers maybe a thousand times as fast,
13:24we can really use this for film production.
13:27In the next five to ten years,
13:29it's going to be possible to do very realistic simulations of light
13:33in real time, interactively.
13:36And video games are going to start looking that much more realistic.
13:40It'll just look like the real world if you want it to.
13:42Physics doesn't just have to be about simulating light.
13:46It can also be about simulating dynamics.
13:48And we're seeing more and more dynamic simulations of how fluids work,
13:52of how objects can break apart,
13:55about how creatures can have flesh
13:59that actually jiggles and distorts in more realistic ways.
14:03Like in the movie Rise of the Apes,
14:07the chimpanzees,
14:08there's actually very complicated physics
14:11simulating how their mouth moves
14:12and how the skin folds and wrinkles around there.
14:16It creates a more believable performance
14:18when Andy Serkis drives these characters
14:21because you actually feel this is organic material
14:24that's moving with muscles underneath.
14:26And it's all being made possible
14:28by better understandings of physics
14:30and much faster computers.
14:32This is what's hot right now.
14:38So these are cool guys.
14:41You got to try to kind of set them in a little bit
14:43and then,
14:43let's check it out as hot fries and stuff again.
14:43So the funding will make me
14:44for sure to get started with sprung.
14:44and I don't think to be that ready for trung on this.
14:44No matter how serious
14:44You have one of those races
Commenti